Conventionally a linerless label has been developed. The linerless label does not include a sheet to be separated (a so-called liner). The sheet is temporarily attached to the rear face of an adhesive layer of the label. Such a linerless label is expected to be a resource-saving material because it does not have a liner that will be discarded after use (see Laid open patent publication JP 2011-31426 A, for example).
FIG. 5 is a perspective view of a conventional linerless label 1 that is wound into a roll. As shown in FIG. 5, this linerless label 1 includes a label base 2, an adhesive layer 3 on the rear-face side, a thermosensitive color developing layer 4 on the front-face side, and a transparent separation agent layer 5 on the top of these layers.
The label base 2 has a location detection mark 6 preprinted on the rear face.
The label base 2 may have fixed information (not illustrated) preprinted on the surface as needed. The fixed information may be a mark indicating the label user, the name, and/or other designs.
This linerless label 1 may be separated into a single label piece 1A by cutting it at cutting lines 7 at predetermined intervals.
FIG. 6 is a schematic side view of a conventional thermal printer 8. The thermal printer 8 has a function of printing variable information on the linerless label 1. Variable information may be information on a commodity information, such as the price and a barcode, or management information on goods or services, for example. The thermal printer 8 includes a feed part 9, a guide part 10, a detection part 11, a print part 12, and a cutting part 13.
The feed part 9 is configured to hold a roll-shaped linerless label 1 and to release the linerless label 1 in a belt-shaped toward the guide part 10, the detection part 11, the print part 12 and the cutting part 13.
The guide part 10 includes a guide roller 14. Such a guide part 10 is configured to guide the released linerless label 1 toward the detection part 11 and the print part 12.
The detection part 11 includes a location detection sensor 15. The detection part 11 is configured to detect a location detection mark 6 on the rear face of the linerless label 1 so as to detect the location of the linerless label 1 (label piece 1A) relative to the print part 12.
The print part 12 includes a thermal head 16 and a platen roller 17. The print part 12 is configured to pinch the linerless label 1 between the thermal head and the platen roller with a predetermined print pressure. The print part 12 is configured to rotary-drive the platen roller 17 at a fixed speed. The print part 12 is configured to supply print data to the thermal head 16 to let the thermosensitive color developing layer 4 develop colors. In this way, the print part 12 can print predetermined variable information on the linerless label 1 (label piece 1A).
The cutting part 13 includes a fixed blade 18 and a movable blade 19. The cutting part 13 is configured to cut the printed linerless label 1 at a part corresponding to the cutting lines 7 at predetermined intervals when the linerless label 1 is transferred between these blades, and to eject the label pieces 1A.
In the thermal printer 8 having such a configuration, the platen roller 17 to transfer the linerless label 1 for printing is a roller made of an elastic body such as rubber member, for example. In order to avoid sticking of the adhesive of the adhesive layer 3 to the roller, such a roller may be made of a silicone rubber member having non-stick property or a rubber member impregnated with silicone oil. Silicone oil may be applied to the peripheral surface of the platen roller 17 for this purpose.